Indices of Refraction: ---------------------- material index material index -------------------------------------------------------------------------------------- acetone 1.36 helium (gas) 1.000036 air (–15 °C) 1.00030942 helium (liquid) ???? air (–00 °C) 1.00029238 hydrogen (gas) 1.000140 air (+15 °C) 1.00027712 hydrogen (liquid) 1.0974 air (+30 °C) 1.00026337 lucite 1.495 air (+60 °C) 1.00023958 milk 1.35 alcohol, ethyl (grain) 1.361 oil, microscope 1.515 alcohol, methyl (wood) 1.328 oil, vegetable (50 °C) 1.47 amber 1.546 opticon (epoxy) 1.545 amethyst 1.544 perovskite 2.38 benzene 1.501 plexiglas 1.488 calcite 1.486 quartz, crystalline 1.544 diamond 2.417 quartz, fused 1.45843 eglestonite 2.49 ruby 1.76 emerald 1.576 salt 1.516 emerald, synth flux 1.561 sapphire 1.76 emerald, synth hydro 1.568 sphalerite 2.428 eye, cornea 1.38 topaz 1.62 eye, aqueous humor 1.33 turpentine 1.472 eye, lens cover 1.38 ulexite 1.49 eye, lens 1.41 vacuum 1 eye, vitreous humor 1.34 water (ice) 1.309 fluorite 1.387 water (liquid, 000 °C) 1.33346 franklinite 2.36 water (liquid, 020 °C) 1.33283 glass, borosilicate (pyrex) 1.474 water (liquid, 100 °C) 1.31766 glass, crown (soda-lime) 1.512 water (vapor) 1.000261 glass, flint (29% lead) 1.569 zircon, high 1.960 glass, flint (55% lead) 1.669 zircon, low 1.920 glass, flint (71% lead) 1.805 zirconia, cubic 2.173 glass, fused silica 1.459 glass, glycerin 1.473 Reference(s): ------------- http://hypertextbook.com/physics/waves/refraction/